Nevada State Gemstone or Gem

Virgin Valley Black Fire Opal

Adopted on May 27, 1987

Nevada's state precious gemstone is the black fire opal. Considered one of the most beautiful of Nevada's gemstones, Virgin Valley black fire opal was designated the precious gemstone.

Northern Nevada's Virgin Valley is the only place in North America where black fire opal is found in any significant quantity. Many pieces contain brilliant pinfire which rivals the Australian opals in play of color. Most of this opal comes from limbs of pines and other conifers (even sagebrush) and some comes in clams, pine cones, vertebrate bones, and other weird forms.

Opal is usually white, clear, pale red or black, and emits brilliant flashes of multi-colored light. Watching the fire in an opal is enchanting.

Opal is a non-crystalline form of the mineral silica which, despite its amorphous structure, displays an amazing degree of internal organization. Opal is related to its more commonly found but highly crystalline cousins quartz and agate, and is formed from amorphous "balls" or lumps" of silica rather that from ordered, naturally faceted crystals.

The most striking quality of opal is its ability to refract and reflect specific wavelengths of light. In fact, the term "opalescence" was coined to describe this phenomenon. The size and spacing of the amorphous spheres of silica within the stone refracts specific wavelengths of light; each sphere refracting a single, pure spectral color much like the individual microscopic droplets of water in a rainbow. The interplay of these pure wavelengths of light gives opal its unique visual appeal, and makes it one of the most sought-after gemstones in the world.